• 한국연소학회지
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• 제15권3호
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• pp.40-47
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• 2010

Calorific value of mixed gas, like liquefied natural gas (LNG), is strongly depends on its compositions which are affected by the mining place and producing time. The variation in calorific value have an direct influence on the combustion characteristics and performances of boiler, burner, vehicle, power plants etc. Thus, developing experimental method to measure exact calorific value is becoming an issue in the related industrial fields. Flame calorimeter is developed to get calorific value at the dynamic equilibrium state using electric substitution method. Refrigerant-11 carries heat from combustor and/or heater to the Peltier elements which pumped it out to the cooling water. It is found out that error in the measured calorific value of methane is 2.86% compared with the theoretical one. Developed design technique and the experimental data will be applied to design the national standard gas calorific value measuring apparatus.

• 도시과학
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• 제8권1호
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• pp.45-49
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• 2019

The land treatment of sewage sludge is necessary because sewage sludge is increasing year by year. Therefore the research of sewage sludge solidification is underway as one of the land treatment methods. However, the problem with existing sewage sludge solidification is that the moisture content of sewage sludge is high and the dewaterability is low. Because of high drying cost the efficiency of energy production is low and the calorific value is insufficient. So the disposer is supplied with a filtration and caloric aid for improving dewaterability and calorific value. In this study, it is aimed to improve the fuel value of sewage sludge by confirming the feasibility of waste wood as a filtration and caloric aid. The dewaterability was measured by CST-test and the calorific value was measured by bomb calorimeter. As a result the dewaterability and calorific value are improved in all of the samples. The dewaterability was improved as the waste wood was added in the sewage sludge. By adjusting the waste wood adding rate into the sewage sludge the dewaterability and calorific value of sewage sludge will be improved. This study confirmed possibility of the waste wood used as filtration and caloric aid.

• Journal of the Korean Wood Science and Technology
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• 제44권6호
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• pp.864-871
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• 2016

This study was conducted to compare and analyze gross calorific values from measurement methods of lignocellulosic biomass and calculation data from calorific value prediction models based on the elemental content. The deviation of Liriodendron tulipifera (LT) and Populus euramericana (PE) was shown 7.7 cal/g and 7.4 cal/g respectively in palletization method, which are within repeatability limit 28.8 cal/g of ISO FDIS 18125. In the case of Thailand charcoal (TC), nontreatment method and palletization method was satisfied with repeatability limit as 22.8 cal/g and 8.8 cal/g respectively. Seowon charcoal (SC) was shown deviation of 11.4 cal/g in nontreatment method, because the density and chemical affinity of sample increases as the carbon content increases from heat treatment at high temperature in the case of TC and SC. In addition, after applying the elemental content of each of these samples to the calorific value prediction models, the study found that Model Equation (3) was relatively consistent with measured calorific values of all these lignocellulosic biomass. Thus, study about the correlation between the density and size of particle should be conducted in order to select the measurement method for a wide range of solid biofuels in the future.

• Journal of Forest and Environmental Science
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• 제31권4호
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• pp.272-279
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• 2015

Xanthoceras sorbifolium is considered as bio-energy crops owing to the high oil content from kernel. This study was performed to analyze calorific value, crude ash content, ultimate ratio, crude lipid and fatty acid composition among seed sources. Calorific values ranged from $4,526.0\;cal\;g^{-1}$ to $7,377.2\;cal\;g^{-1}$ in seeds and kernels showed the highest value. Calorific values and crude ash contents were observed as significant difference among plantations and/or individuals (p>0.05). Kernel from SD-F plantation showed the highest calorific value and lower crude ash content. C content comprised 63.4%, the highest levels was detected from SD-F (64.8%). Crude lipid content in kernel observed as 54.5 g $100\;g^{-1}$ from SD-F. In contrast it was determined the lowest value from LN-JARS as 46.5 g $100\;g^{-1}$. The fatty acid composition of kernel was determined to those of oleic acid (31.3%) and linoleic acid (38.1%) from SD-F and LN-JARS. These results will be offered to useful information for breeding materials selection.

• 농업과학연구
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• 제38권4호
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• pp.619-624
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• 2011

The calorific value is the most significant factor in woody biomass utilization. We measured the calorific value by the wood parts (debarked parts and bark) and moisture content for 3 major tree species (Larix kaempferi, Pinus koraiensis, and Pinus rigida). Results showed that the calorific value decreased exponentially as the moisture content increased regardless of tree species and the wood parts. The bark had higher calorific values than woody parts (de-barked parts). In addition, Pinus koraiensis had the highest calorific values among 3 study species.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.135-136
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• 2017

This paper examines the efficiency of the application of conventional and insulated gang forms for curing and protection of concrete by comparing the amount of electric energy required therefor. In addition, a thermal vision camera was used to identify heat loss from surfaces of the gang forms after each placement of concrete. Experimental results, show that the heat loss at the submerged temperature was large at the submerged surface due to the large calorific value at the surface of the mold. The insulated gang form had some heat loss in the horizontal bars. In the case of adiabatic reforming, the pattern shows a constant calorific value over time. In conclusion, the insulation performance is better than that of general gang form.

• 한국대기환경학회지
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• 제30권4호
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• pp.301-310
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• 2014

Country-specific data for net calorific values and carbon emission factors requires for a higher tier estimate of greenhouse gas emissions in the energy sector. The objective of this study is to develop country-specific net calorific values and carbon emission factors for petroleum energy produced in Korea. Calorific values and carbon contents of the fuels were measured using the oxygen bomb calorimeter method and the CHN elemental analysis method, respectively. Sulfur and hydrogen contents, which were used to calculate the net calorific value, were also measured and then net calorific values and carbon emission factors were determined based on the measurement results. The net calorific values and carbon emission factors determined for the petroleum produced in Korea 2012 and 2013 were compared to those in the 2006 IPCC Guidelines. Most of the values were different compared with the default values of the 2006 IPCC Guidelines although those were placed within their upper and lower limits. Time series analysis results showed inconsistent seasonal variation for the net calorific values and carbon emission factors.

• 동력기계공학회지
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• 제21권5호
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• pp.55-62
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• 2017

In this study, the water content and the low calorific value of the dried sludge are analyzed by using a vertical cylinder type indirect heating type dryer for evaluatation of energy source value. The vertical cylindrical thin film dryer was an Okadora Pilot Plant, and the dryer was indirect heating vertical thin film type. The internal standard consisted of 500 mm in diameter and 700 mm in height. In the drying experiment, 10 kg of dehydrated sewage sludge was added to the dryer and the total amount of the sludge was adjusted to 27 times by variable of the time, the number of revolutions and the steam temperature. The results of analysis of the 27th experiment component of the dried product showed that the average low calorific value of about 11.2 MJ/kg and the water content of 6%. This is satisfy the fuel use standard of the thermal power plant of the sludge.

• Journal of the Korean Wood Science and Technology
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• 제51권5호
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• pp.381-391
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• 2023

Densification is a technique used to improve biomass quality in wood pellet manufacturing and torrefaction treatment. In this study, the effects of torrefaction on the quality of Calliandra wood pellets were investigated, and pellets of Calliandra wood (Calliandra calothyrsus) and bark were evaluated. The study was conducted using a completely randomized design with two treatment factors, namely torrefaction temperature (250℃ and 300℃) and torrefaction duration (30, 45, and 60 min). The results showed that the interaction between temperature and torrefaction duration significantly affected the compressive strength, proximate value, and calorific value of the torrefied Calliandra wood pellets. An increase in the temperature and torrefaction duration decreased the compressive strength, moisture content, volatile matter content, and ash content of the torrefied Calliandra wood pellets. Conversely, the calorific value of Calliandra wood pellets increased with increasing temperature and torrefaction duration. The best-quality Calliandra wood pellets were produced at a torrefaction temperature and duration of 300℃ and 60 min, respectively. In terms of important quality parameters, ash content of 0.90% and calorific value of 6,303.80 cal/g were observed, which complied with the quality standards of Indonesian National Standard 8675:2018 and Deutsche Industrie Norm 51731.

• 한국응용과학기술학회지
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• 제34권4호
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• pp.1046-1057
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• 2017

국가 온실가스 인벤토리를 Tier 2 이상의 수준으로 향상시키기 위해서는 IPCC 기본값 대신 국가 고유의 배출계수가 개발 및 이용되어야 한다. 국가 고유 배출계수는 에너지원 종류, 에너지 공정, 시간 추세에 따라 달라지기 때문에, 각 에너지원별 특성값을 파악하는 것은 정확한 인벤토리 구축에 중요한 부분을 차지한다. 국내 석유계 에너지원의 물성은 시간의 경과에 따라 큰 변화는 없었으며, 국내에서 고시되고 있는 에너지원별 열량환산기준 상의 석유계 에너지원에 대한 열량 및 탄소배출계수를 2013년과 2016년에 실제 시료를 수집하여 발열량, 탄소함량 및 탄소배출계수를 산정한 결과값과의 비교분석에서는 대체적으로 일정한 값을 유지하고 있는 것으로 나타났다. 또한, 석유계 에너지원별로 산출된 순발열량과 탄소배출계수는 2006 IPCC Guideline에 나타낸 값들과 비교하였으며, 대부분의 에너지원이 2006 IPCC G/L의 기본값 및 상한, 하한 범위내의 값을 나타내었다.